Dragon fruit is gradually making its way into the fields by winning the hearts of farmers through its immense popularity. Dragon fruit (Hylocereus spp.), also referred to as pitaya or pitahaya, is a kind of vine cactus that is native to South America and is typically found growing in tropical climates, such as Southeast Asia (Athira and Mini, 2024; Liaotrakoon et al., 2013; Patwary et al., 2013). This high value fruit is well accepted worldwide due to its nutritional importance. Two genotypes of the Hylocereus species, namely Hylocereus costaricensis (red fleshed dragon fruit) and Hylocereus undatus (white fleshed dragon fruit), are introduced in Bangladesh (Rifat et al., 2019). Dragon fruit has a wide adaptation range hence it can easily be grown in different corners of the world. The attractive color and taste of dragon fruit pulp rich in water-soluble fiber, vitamin C and antioxidants including Betalains, hydroxycinnamates and flavonoids, make it very attractive (Moshfeghi et al., 2013). It helps in weight loss, enhances digestion, lowers blood LDL cholesterol and strengthens the immune system, in order to lower the risk of heart disease, flavonoids and hydroxycinnamates work on blood vessels and brain cells, respectively. Moreover, it protects against germs and fungus and supports the body’s general function (Verma et al., 2017). The fruit species of Hylocereus are rich in phytochemicals, antioxidants, calcium, phosphorus, magnesium, fiber and vitamins (Pavithra and Mini, 2023; Mahdi et al., 2018; Sushmitha et al., 2018). The production of this fruit is expanding quickly all over the world because of its health benefits, as well as the wealth of vitamins and nutrients (Mazid et al., 2025). The favorable tropical climate in Bangladesh has led to an increase in the production of dragon fruit. In 2014, Bangladesh produced only 66 tons of dragon fruit on 18 hectares of land, according to the Horticulture Wing of the Department of Agricultural Extension (DAE). In fiscal 2020-21, farmers grew pitaya on 695 hectares of land to bag 8,660 tons of the fruit, which is more than double the total yield of 3,463 tons the previous year. Seeing their success, more farmers in other regions are now trying to grow the fruit.
       
Dragon fruit cultivation has gained significant attention among farmers in Bangladesh due to its potential as a novel and profitable crop. However, the country’s limited arable land and high population density (Population and Housing Census, 2022) pose challenges to dedicating land solely to dragon fruit cultivation. In this context, adopting integrated farming systems such as the aonla-based multistoried production model is crucial (Reza et al., 2022). This climate-smart agro-technology not only optimizes land use but also mitigates the adverse effects of climate change by providing diverse benefits. While both red and white dragon fruit genotypes have been successfully cultivated in this multistoried system without compromising fruit yield compared to open-field conditions, the impact of shaded environments on the biochemical composition of dragon fruit has not been previously explored. Under-standing how shade levels affect the nutritional quality of dragon fruit grown in multistoried systems is essential for promoting this sustainable cultivation method. This study aims to fill this knowledge gap by assessing the biochemical composition and quality attributes of dragon fruit genotypes under varying shade levels, thereby contributing to the development of sustainable and efficient production practices in Bangladesh.
 

Location and experimental design
 
This location of the experiment was between the longitudes of 90.25° E and 24.09° N and it was 8.5 meters above sea level (Reza et al., 2024). The sample fruits were collected between July 2021 and June 2023 from existing multistory fruit production model (Fig 1), which is based on aonla, carambola, lemon and dragon fruit research plot of the Department of Agroforestry and Environment, Gazipur Agricultural University, Gazipur-1706. Three replications of a two-factor randomized complete block design were used to examine the quality attributes of dragon fruit at the Agro-processing laboratory. An experiment as conducted using two factors viz., Factor A: Fruit production model T₁: Aonla + Carambola + Lemon + Dragon fruit (multistoried), T₂: Aonla + Dragon fruit (double storied) and T₃: Dragon fruit (sole cropping); Factor B: Dragon fruit genotypes, V₁: Red fleshed dragon fruit and V₂: White fleshed dragon fruit. A total 36 number of samples were used throughout the experiment.


 
Physical attributes measurement
 
The incidence of sunlight on dragon fruit was measured using a sunflex ceptometer (LP-80 AccuPAR) to determine the shading levels created by various tree species, expressed as mol m^-2s^-1. After harvest, the fruit weight, length and breadth were recorded.
 
Proximate content analysis
 
Proximate parameters analyzed in the study included moisture content, total soluble solids (TSS), total sugar, reducing sugar, non-reducing sugar, fat, fibre, protein, ash and carbohydrate. The moisture was determined using the gravimetric method described in (Ranganna, 2015). TSS was measured using a digital refractometer (HI 96801, HANNA Instruments). Total sugar, reducing sugar and non-reducing sugar content were estimated using Fehling’s titration method, with a standard sugar solution for calibration (Ranganna, 2015). Fat content was estimated using a Soxhlet apparatus, where fat was extracted with petroleum ether at 70-80°C for 8 hours (Ranganna, 2015). Fiber content was measured as crude fiber by sequentially treating the sample with dilute sulfuric acid and sodium hydroxide solutions. Protein content was calculated by estimating nitrogen using the Kjeldahl method (Ranganna, 2015). Ash was estimated by burning samples at 550°C in a muffle furnace until constant weight was achieved. Total carbohydrate content of the samples was calculated by difference, that is, by subtracting the measured protein, fat, ash and moisture content (Pearson, 1976).
 
Determination of pH and vitamin C
 
The pH of the dragon fruit samples was determined by using a pH meter (Model: LE pH Electrode LE438-IP67, Mettler Toledo, Hong Kong). The ascorbic acid content was determined using the 2,6-dichlorophenol-indophenol visual titration method as described by (Ranganna, 2015).
 
Determination of minerals
 
Sodium (Na), magnesium (Mg), calcium (Ca) and Potassium (K) were determined using Atomic Absorption Spectrometer (Model- PinAAcle 900H) at specific wavelengths for each mineral according to Sanchez-Castillo et al., 1998.
 
Measuring the energy content
 
Total calories of samples were estimated using an oxygen bomb calorimeter (Model: 1341, Parr Instrument Company, USA).
 
Data analyses
 
MS-Excel, STATISTX 10 and R software (version 4.3.2) were used to process, calculate and analyze the data. To compare the treatment means, the necessary tests were run. Least Significant Difference (LSD) was used to adjust the mean differences at 5% and 1% level of significance.

Photosynthetically active radiation (PAR) distribution
 
The T₃ treatment (dragon fruit sole) had the highest mean maximum light intensity (1503.36 μmol m^-2 s^-1), followed by the T₂ treatment (aonla + dragon fruit) at 1181.70 μmol m^-2 s^-1 and the T₁ treatment (multistoried system) at 1128.22 μmol m^-2 s^-1. The PAR received by the T₁ and T₂ was 75 and 78.60%, respectively. Due to variation of the canopy density over storied tree species light variation has occurred on dragon fruit (Fig 2).


 
Fruit length, diameter and weight
 
The interaction of the multistoried fruit production model and dragon fruit genotypes significantly affected fruit length, diameter and weight (Fig 3). The longest fruit (8.74 cm) was observed in the T₁V₂ combination (white-fleshed genotype in multistoried), while the smallest (7.92 cm) was in T₃V₁. The multistoried system (T₁V₁) produced the widest fruit (11.66 cm), while the narrowest was in T₃V₁ (7.92 cm). Red-fleshed genotypes produced larger, wider fruit (261.67 g in T₁V₁). The multistoried system yielded larger fruit (154.34 g in T₃V₂) due to fewer fruits per plant, increasing individual fruit weight (Reza et al., 2022).


 
Moisture level
 
The moisture contents of dragon fruit in different treatments and genotypes were given in Table 1. The white fleshed genotype had the maximum moisture content (86.36%) in the T₃V₂ treatment, moderate moisture content was found in T₂V₂ treatment and in T₁V₂ treatment. The lowest moisture content was found in the red fleshed genotype of dragon fruit in T₃V₁ (84.10 %) and in T₂V₁ (84.16 %) treatments, respectively. According to (Nomura et al., 2005 and Sonawane, 2017) the moisture percentage of dragon fruit was 83-89%, which was roughly close to the dragon fruit used in the study.


 
pH
 
pH is the measurement of acidity or alkalinity of a product. pH of dragon fruit samples was not significantly varied and the value ranged from 4.63 to 4.66 (Table 1). According to Sonawane, (2017) and Nomura et al., (2005) dragon fruit pH range was 4 to 6 which supports the present findings.
 
Brix content
 
The highest TSS (25.28%) was recorded in the T₃V₁ treatment, followed by T₁V₁ and T₂V₁. The lowest TSS (23.06%) was found in T₃V₂, which was statistically similar to T₁V₂ (23.11%) and T₂V₂ (23.10%). These results suggest that red dragon fruit, with higher TSS content, is sweeter than white-pulped varieties. Mallik et al. (2018) reported that TSS in dragon fruit ranges from 23.10% to 27.17%, with fruit setting times significantly influencing TSS content.
 
Energy content
 
Energy measurement is crucial for dietary balance. T₂V₁ had the highest energy content (62.70 Kcal/100 g), followed by T₃V₁ (62.50 Kcal/100 g), while T₂V₂ had the lowest (40.40 Kcal/100 g) (Table 1). Red-fleshed dragon fruit had higher energy content than the white-fleshed variety. Patel and Ishnava, (2019), Nurul and Asmah, (2014) and Wichienchot et al. (2010) reported 60 Kcal/100 g in fresh dragon fruit.
 
Sugar content
 
The highest total and reducing sugar were in T₁V₁, followed by T₂V₁ and T₃V₁, while T₁V₂ had the lowest (Table 1). T₂V₁ had the highest non-reducing sugar and T₁V₂ the lowest. Shaded conditions in multistoried models may enhance sweetness. Red dragon fruit, with higher TSS, had more sugar than the white variety (Liaotrakoon et al., 2013). Nurul and Asmah, (2014) noted that the growing environment significantly affects dragon fruit’s nutritional and phytochemical composition.
 
Fat content
 
Both the dragon fruit genotypes contain 0.395 g/100 g fat in all the three treatments (Table 1). According to Sonawane, (2017) the fat level of dragon fruit was 0.4 g/100 g which was roughly similar to the dragon fruit that was studied.
 
Carbohydrate content
 
Energy measurement is crucial for dietary balance. T₂V₁ had the highest energy content (62.70 Kcal/100 g), followed by T₃V₁ (62.50 Kcal/100 g), while T₂V₂ had the lowest (40.40 Kcal/100 g) (Table 1). Red-fleshed dragon fruit had higher energy content than the white-fleshed variety. Patel and Ishnava, (2019); Nurul and Asmah, (2014) and Wichienchot et al. (2010) reported 60 Kcal/100 g in fresh dragon fruit.
 
Fiber content
 
Dragon fruit’s highest fiber content was in T₃V₁ (0.68 g/100 g), moderate in T₂V₁ (0.55 g) and lowest in T₃V₂ (Table 1). Red-fleshed dragon fruit had more fiber, likely due to genetics. Liaotrakoon et al. (2013) reported fiber content ranging from 0.5-0.7 g/100 g, supporting this study.

Protein content
 
Protein content of dragon fruit varied from 1.17 to 1.11 g among all the treatment combinations and there was no significant difference found. (Table 1). According Sonawane, (2017) protein content of dragon fruit was 0.50 to 1.10 g/100 g fresh sample which supports the result.
 
Ash level
 
T₃V₁ has noticeably the greatest ash content (1.80 g/100 g) and the lowest ash content was found in T₃V₂ (1.60 g/100 g) treatment combination (Table 1). Red fleshed dragon fruit genotype produced comparatively higher amount of ash than white one irrespective of treatments. This variation in ash content might be due to the genetic make-up of dragon fruit genotypes. According to Kishore, (2016) ash content of dragon fruit varies from 1.50 g to 2.00 g which was approximately similar to that of the result.

Vitamin C content
 
Treatment combinations significantly affected vitamin C content in dragon fruit. T₃V₁ had the highest (25.12 mg/100 g), while T₁V₂ had the lowest (22.79 mg) (Table 1). Full sun exposure increased vitamin C levels. Sumaryani and Dharmadewi, (2018) reported 29.00 mg in red-fleshed and 22.30 mg in white-fleshed dragon fruit. Sonawane, (2017) found 20.50 mg, while Kishore, (2016) reported 25.00 mg, aligning with the present study.
 
Mineral composition
 
Minerals are essential for health, classified as macro and trace elements. The T₁V₁ treatment yielded the highest mineral content in dragon fruit, with K (5.80 mg) being the highest, followed by Mg and Na, while Ca was lowest (0.76 mg). All treatments showed a similar trend (K > Mg > Na > Ca), likely influenced by genotype and shading (Table 2). Liaotrakoon et al. (2013) noted that genotype and flowering time affect fruit growth, size and nutritional quality.


 
Nutritional comparison of dragon fruit genotypes
 
Two dragon fruit genotypes showed significant nutritional differences under various treatments (Table 3). The red-fleshed genotype had higher moisture, TSS, energy, sugars, fiber and vitamin C than the white-fleshed type. Mineral content also varied significantly (Table 3), with red-fleshed dragon fruit containing more Na (1.58 mg/g), while the white-fleshed type had slightly higher Ca (0.66 mg/g), K (6.31 mg/g) and Mg (3.20 mg/g), likely due to genetic factors. Liaotrakoon et al. (2013) noted species, origin and harvest time influence nutritional quality, while Nurul and Asmah, (2014) highlighted environmental effects. The correlation heat map (Fig 4) reveals strong positive and negative relationships, including a significant negative correlation between fiber and sodium (r = -0.96) and a strong positive correlation between total sugar and energy content (r = 0.99).




 
Biplot principal component analysis
 
The first two principal components (PC1: 67.1%, PC2: 9.0%) explain 76.1% of the total variance (Fig 5). The PCA biplot reveals six distinct clusters representing dragon fruit genotypes and treatments. Genotypes V₁ and V₂ are clearly separated, indicating significant differences. Treatments 2 and 3 enhance ash content and vitamin C, while treatment 1 boosts total and reducing sugars in V₁. In V₂, treatment 3 improves mineral traits like calcium and magnesium, aiding treatment optimization.

Dragon fruit is a fruit of full sun light, but this fruit can be cultivated in 75-78.6% shade condition in multistoried fruit production model. Cultivation in shade does not spoil the nutritional quality of this fruit although multistoried fruit production model with maximum shade produces large (261.67 g) and sweet (TSS, 25%) dragon fruit than open field condition where plants get full sunlight. Double storied system where 78.60% shade produces almost same quality fruits like open field condition. The studied nutritional quality parameters vary between red fleshed and white fleshed genotypes of dragon fruit and red fleshed genotype of dragon fruit found superior than white fleshed genotype in content nutrients but minerals like Ca, Mg and K are slightly higher in white flesh genotype of dragon fruit than red one.

The Research Management Wing of Gazipur Agricultural University provided logistic support for this study.

The authors declare that there are no conflicts of interest regarding the publication of this article. No funding or sponsorship influenced the design of the study, data collection, analysis, decision to publish, or preparation of the manuscript.